These alarms are sent by MSA when the below condition is hit.
Explanation of Bitmap On Frequency and Back Pressure On Frequency
Bitmap On Frequency
The percentage of operating time that data could not efficiently reach the DRVA, so newly written data was captured by the IO filters in bitmaps for later replication.
Bitmap mode warning: This alarm will be triggered if a domain stays in bitmap mode for a period exceeding 5 consecutive minutes.
Cause of the alarm:
Network disruption between DRVA and the object store.
When the Replication Log is fully occupied and no space left.
Note: DRVA network statistics can be checked from the vCenter.
Back Pressure On Frequency
The percentage of operating time the application writes operations were slowed to accommodate data replication.
BackPressure alarm: This alarm will be triggered if the application write backPressure has been applied for a period exceeding 5 consecutive minutes.
Cause of this alarm:
When the Replication incoming data rate is more than the outgoing.
Note: The Network Statistics of a Protected VM and DRVA can be verified From the vCenter level to isolate the issue.